COMPOSITION AND SOME STRUCTURAL FEATURES OF PRINCIPAL GASTRIC GLYCOPROTEIN

Gel chromatography on Sephadex G 150 or Bio-gel P150 resolved the gastric secretions into three fractions. The non-retarded fraction contained 70-90% of the total carbohydrate eluted in the three fractions. The gastric secretions before gel filtration and the non-retarded fraction contained the same carbohydrate residues and the three carbohydrate components, galactose, glucosamine and galactosamine, in the same quantitative proportions. The amino-acid composition of the non-retarded fraction showed marked similarities and characteristic quantitative relationships. Threonine and serine were found to constitute 45-50% of the total aminoacid content. The analytical data, ultracentrifugation and light scattering studies suggest that the non-retarded fraction is composed of macromolecules which have a common basic composition but which arc polydisperse with reference to their charged end groups, fucose and size. © 1969 S. Karger AG, Basel.